//主键

[Key]

public Guid Id { get; set; }

//自增主键 

[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]

public Guid UserGuid { get; set; }

//可空字段

public Guid? TenantId { get; set; }

//非空字段

[Required]

public int RechargeDays { get; set; }

//固定类型

[Column(TypeName ="datetime")]

public System.DateTime RechargeTime { get; set; }

//固定类型与长度

[Column(TypeName ="nvarchar(200)")]

public string Remark { get; set; }

//最大 最小长度

[MaxLength(30), MinLength(5)]

public string CategoryName { get; set; }